maint: Change Guix System file names from guixsd-*.

* Makefile.am (GUIXSD_SUPPORTED_SYSTEMS): Rename to...
(GUIX_SYSTEM_SUPPORTED_SYSTEMS): ... this.
(GUIXSD_VM_SYSTEMS): Rename to...
(GUIX_SYSTEM_VM_SYSTEMS): ... this.
(GUIXSD_IMAGE_BASE): Rename to...
(GUIX_SYSTEM_IMAGE_BASE): ... this.  Change "guixsd-" to "guix-system-".
(GUIXSD_VM_IMAGE_BASE): Rename to...
(GUIX_SYSTEM_VM_IMAGE_BASE): ... this.  Change "guixsd-" to
"guix-system-".
(release): Adjust accordingly.
* doc/guix.texi (USB Stick and DVD Installation)
(Installing Guix in a VM, Invoking guix system)
(Running Guix in a VM): Adjust file names accordingly.

Makefile.am

@@ -661,17 +661,17 @@ SUPPORTED_SYSTEMS ?= x86_64-linux i686-linux armhf-linux aarch64-linux
 BINARY_TARBALLS =							\
   $(foreach system,$(SUPPORTED_SYSTEMS),guix-binary.$(system).tar.xz)
 
-# Systems supported by GuixSD.
-GUIXSD_SUPPORTED_SYSTEMS ?= x86_64-linux i686-linux
+# Systems supported by Guix System.
+GUIX_SYSTEM_SUPPORTED_SYSTEMS ?= x86_64-linux i686-linux
 
-# Systems for which we build GuixSD VMs.
-GUIXSD_VM_SYSTEMS ?= x86_64-linux
+# Systems for which we build Guix VMs.
+GUIX_SYSTEM_VM_SYSTEMS ?= x86_64-linux
 
-# Prefix of the GuixSD installation image file name.
-GUIXSD_IMAGE_BASE = guixsd-install-$(PACKAGE_VERSION)
+# Prefix of the Guix installation image file name.
+GUIX_SYSTEM_IMAGE_BASE = guix-system-install-$(PACKAGE_VERSION)
 
-# Prefix of the GuixSD VM image file name.
-GUIXSD_VM_IMAGE_BASE = guixsd-vm-image-$(PACKAGE_VERSION)
+# Prefix of the Guix VM image file name.
+GUIX_SYSTEM_VM_IMAGE_BASE = guix-system-vm-image-$(PACKAGE_VERSION)
 
 # The release process works in several phases:
 #
@@ -680,7 +680,7 @@ GUIXSD_VM_IMAGE_BASE = guixsd-vm-image-$(PACKAGE_VERSION)
 #   2. Update the 'guix' package so that it corresponds to the 'vX.Y' tag.
 #   3. Build the binary tarballs for that 'guix' package.
 #   4. Update the 'guix' package again.
-#   5. Build the GuixSD installation images.  The images will run 'guix'
+#   5. Build the installation images.  The images will run 'guix'
 #      corresponding to 'vX.Y' + 1 commit, and they will install 'vX.Y'.
 #
 # This 'release' target takes care of everything and copies the resulting
@@ -713,32 +713,32 @@ release: dist
 	   "`git rev-parse HEAD`"
 	git add $(top_srcdir)/gnu/packages/package-management.scm
 	git commit -m "gnu: guix: Update to `git rev-parse HEAD | cut -c1-7`."
-	for system in $(GUIXSD_SUPPORTED_SYSTEMS) ; do					\
+	for system in $(GUIX_SYSTEM_SUPPORTED_SYSTEMS) ; do				\
 	  image=`$(top_builddir)/pre-inst-env						\
 	    guix system disk-image							\
 	    --file-system-type=iso9660							\
             --system=$$system								\
 	    gnu/system/install.scm` ;							\
 	  if [ ! -f "$$image" ] ; then							\
-	    echo "failed to produced GuixSD installation image for $$system" >&2 ;	\
+	    echo "failed to produced Guix installation image for $$system" >&2 ;	\
 	    exit 1 ;									\
 	  fi ;										\
-	  xz < "$$image" > "$(releasedir)/$(GUIXSD_IMAGE_BASE).$$system.iso.xz.tmp" ;	\
-	  mv "$(releasedir)/$(GUIXSD_IMAGE_BASE).$$system.iso.xz.tmp"			\
-	     "$(releasedir)/$(GUIXSD_IMAGE_BASE).$$system.iso.xz" ;			\
+	  xz < "$$image" > "$(releasedir)/$(GUIX_SYSTEM_IMAGE_BASE).$$system.iso.xz.tmp" ;	\
+	  mv "$(releasedir)/$(GUIX_SYSTEM_IMAGE_BASE).$$system.iso.xz.tmp"		\
+	     "$(releasedir)/$(GUIX_SYSTEM_IMAGE_BASE).$$system.iso.xz" ;		\
 	done
-	for system in $(GUIXSD_VM_SYSTEMS) ; do						\
+	for system in $(GUIX_SYSTEM_VM_SYSTEMS) ; do					\
 	  image=`$(top_builddir)/pre-inst-env						\
 	    guix system vm-image							\
 	    --system=$$system								\
 	    gnu/system/examples/vm-image.tmpl` ;					\
 	  if [ ! -f "$$image" ] ; then							\
-	    echo "failed to produced GuixSD VM image for $$system" >&2 ;		\
+	    echo "failed to produced Guix VM image for $$system" >&2 ;			\
 	    exit 1 ;									\
 	  fi ;										\
-	  xz < "$$image" > "$(releasedir)/$(GUIXSD_VM_IMAGE_BASE).$$system.xz.tmp" ;	\
-	  mv "$(releasedir)/$(GUIXSD_VM_IMAGE_BASE).$$system.xz.tmp"			\
-	     "$(releasedir)/$(GUIXSD_VM_IMAGE_BASE).$$system.xz" ;			\
+	  xz < "$$image" > "$(releasedir)/$(GUIX_SYSTEM_VM_IMAGE_BASE).$$system.xz.tmp" ;	\
+	  mv "$(releasedir)/$(GUIX_SYSTEM_VM_IMAGE_BASE).$$system.xz.tmp"			\
+	     "$(releasedir)/$(GUIX_SYSTEM_VM_IMAGE_BASE).$$system.xz" ;			\
 	done
 	@echo
 	@echo "Congratulations!  All the release files are now in $(releasedir)."

doc/guix.texi

@@ -1866,7 +1866,7 @@ about their support in GNU/Linux.
 
 An ISO-9660 installation image that can be written to a USB stick or
 burnt to a DVD can be downloaded from
-@indicateurl{https://alpha.gnu.org/gnu/guix/guixsd-install-@value{VERSION}.@var{system}.iso.xz},
+@indicateurl{https://alpha.gnu.org/gnu/guix/guix-system-install-@value{VERSION}.@var{system}.iso.xz},
 where @var{system} is one of:
 
 @table @code
@@ -1882,8 +1882,8 @@ Make sure to download the associated @file{.sig} file and to verify the
 authenticity of the image against it, along these lines:
 
 @example
-$ wget https://alpha.gnu.org/gnu/guix/guixsd-install-@value{VERSION}.@var{system}.iso.xz.sig
-$ gpg --verify guixsd-install-@value{VERSION}.@var{system}.iso.xz.sig
+$ wget https://alpha.gnu.org/gnu/guix/guix-system-install-@value{VERSION}.@var{system}.iso.xz.sig
+$ gpg --verify guix-system-install-@value{VERSION}.@var{system}.iso.xz.sig
 @end example
 
 If that command fails because you do not have the required public key,
@@ -1910,7 +1910,7 @@ To copy the image to a USB stick, follow these steps:
 Decompress the image using the @command{xz} command:
 
 @example
-xz -d guixsd-install-@value{VERSION}.@var{system}.iso.xz
+xz -d guix-system-install-@value{VERSION}.@var{system}.iso.xz
 @end example
 
 @item
@@ -1919,7 +1919,7 @@ its device name.  Assuming that the USB stick is known as @file{/dev/sdX},
 copy the image with:
 
 @example
-dd if=guixsd-install-@value{VERSION}.@var{system}.iso of=/dev/sdX
+dd if=guix-system-install-@value{VERSION}.@var{system}.iso of=/dev/sdX
 sync
 @end example
 
@@ -1935,7 +1935,7 @@ To copy the image to a DVD, follow these steps:
 Decompress the image using the @command{xz} command:
 
 @example
-xz -d guixsd-install-@value{VERSION}.@var{system}.iso.xz
+xz -d guix-system-install-@value{VERSION}.@var{system}.iso.xz
 @end example
 
 @item
@@ -1944,7 +1944,7 @@ its device name.  Assuming that the DVD drive is known as @file{/dev/srX},
 copy the image with:
 
 @example
-growisofs -dvd-compat -Z /dev/srX=guixsd-install-@value{VERSION}.@var{system}.iso
+growisofs -dvd-compat -Z /dev/srX=guix-system-install-@value{VERSION}.@var{system}.iso
 @end example
 
 Access to @file{/dev/srX} usually requires root privileges.
@@ -2364,7 +2364,7 @@ Boot the USB installation image in an VM:
 @example
 qemu-system-x86_64 -m 1024 -smp 1 \
   -net user -net nic,model=virtio -boot menu=on \
-  -drive file=guixsd-install-@value{VERSION}.@var{system}.iso \
+  -drive file=guix-system-install-@value{VERSION}.@var{system}.iso \
   -drive file=guixsd.img
 @end example
 
@@ -23360,7 +23360,7 @@ system configuration file.  You can then load the image and launch a
 Docker container using commands like the following:
 
 @example
-image_id="$(docker load < guixsd-docker-image.tar.gz)"
+image_id="$(docker load < guix-system-docker-image.tar.gz)"
 docker run -e GUIX_NEW_SYSTEM=/var/guix/profiles/system \\
     --entrypoint /var/guix/profiles/system/profile/bin/guile \\
     $image_id /var/guix/profiles/system/boot
@@ -23546,7 +23546,7 @@ example graph.
 @cindex virtual machine
 To run Guix in a virtual machine (VM), one can either use the
 pre-built Guix VM image distributed at
-@indicateurl{https://alpha.gnu.org/gnu/guix/guixsd-vm-image-@value{VERSION}.@var{system}.xz}
+@indicateurl{https://alpha.gnu.org/gnu/guix/guix-system-vm-image-@value{VERSION}.@var{system}.xz}
 , or build their own virtual machine image using @command{guix system
 vm-image} (@pxref{Invoking guix system}).  The returned image is in
 qcow2 format, which the @uref{http://qemu.org/, QEMU emulator} can